May Be Caused by

Abscess

Angiomyolipoma

Benign adenomatous neoplasm

Burkitt lymphoma

Clear cell sarcoma

Embryonal adenoma

Fibroepithelial polyp of renal pelvis or ureter

Focal hydronephrosis

Leukemia

Lymphoma

Mesoblastic nephroma

Metastasis

Multilocular cystic renal tumor

Nephroblastomatosis

Nephrogenic adenofibroma

Neuroblastoma

Ossifying renal tumor of infancy

Polycystic kidney disease

Renal cell carcinoma

Renal cyst

Rhabdoid tumor

Rhabdomyosarcoma

Wilms tumor